Present in situ stress measurement in the eastern segment of Yarlung Zangbo River fault and fault activity analysis

Authors

Wei feng SUN, Technology Innovation Center for In-situ Stress , Ministry of Nature Resources, Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, ChinaFollow
Huo lin HUANG, PowerChina Huadong Engineering Corporation Limited, Hangzhou, Zhejiang 311122, China
Dong sheng SUN, Technology Innovation Center for In-situ Stress , Ministry of Nature Resources, Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, ChinaFollow
Wen MENG, Technology Innovation Center for In-situ Stress , Ministry of Nature Resources, Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China
Qun ce CHEN, Technology Innovation Center for In-situ Stress , Ministry of Nature Resources, Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China

Corresponding Author

SUN Dong-sheng

Abstract

In order to determine the in situ stress stat e of the newly built hydropower station project in Jiacha county, and understand the activity of the eastern segment of the Yarlung Zangbo River fault zone, we obtained the in situ stress data in the engineering field by using the self developed deep hole stress measuring equipment based on the hydraulic fracturing method . We analyzed the fault activity by employing the Mohr Coulomb failure criterion and the collected in situ stress data along the eastern segment of the Yarlung Zangbo River fault zone. The results showed that: (1) The magnitude s of the maximum horizontal principal stress S H ranged from 6.07 MPa to 37.62 MPa, the values of the minimum horizontal principal stress S h were from 3.13 MPa to 20.33 MPa at the depth from 122.75 m to 418.75 m, and th e dominant direction of the measured maximum horizontal principal stress was nearly NNE . (2) The stress regime was mainly characterized by SH >Sh >Sv (Sv is the vertical principal stress), which was prone to reverse faulting (3) Most of the measured and collected Mohr stress circles intersected the failure threshold line with friction coefficient equal to 0.6 , which indicated that the eastern se gment of the Yarlung Zangbo River fault zone was in a high level of fault slip instability. Furthermore, the fault slip risk of the west section from Gongga to Langxian was higher than that of the east section near Linzhi along the eastern segment of the Y arlung Zangbo River fault zone.

Graphic Abstract

Recommended Citation

SUN, Wei feng; HUANG, Huo lin; SUN, Dong sheng; MENG, Wen; and CHEN, Qun ce (2024) "Present in situ stress measurement in the eastern segment of Yarlung Zangbo River fault and fault activity analysis," Rock and Soil Mechanics: Vol. 45: Iss. 4, Article 6.
DOI: 10.16285/j.rsm.2023.5545
Available at: https://rocksoilmech.researchcommons.org/journal/vol45/iss4/6